deserveyoudaoicibaDictYouDict
deserve: [13] Latin dēservīre meant ‘serve well or enthusiastically’ (it was a compound verb formed from the intensive prefix - and servīre ‘serve’). Hence in late Latin it came to mean ‘become entitled to because of meritorious service’, a sense which passed via Old French deservir into English. The more general modern English ‘be worthy of’ developed in the 15th century.
=> serve
desert (n.2)youdaoicibaDictYouDict
"suitable reward or punishment" (now usually plural and with just), c. 1300, from Old French deserte, noun use of past participle of deservir "be worthy to have," ultimately from Latin deservire "serve well" (see deserve).
deserve (v.)youdaoicibaDictYouDict
early 13c., from Old French deservir (Modern French desservir) "deserve, be worthy of, earn, merit," from Latin deservire "serve well," from de- "completely" (see de-) + servire "to serve" (see serve). From "be entitled to because of good service" (a sense found in Late Latin), meaning generalized c. 1300 to "be worthy of." Related: Deserved; deserving.
desertsyoudaoicibaDictYouDict
"What a person deserves with regard to reward or (more usually) punishment", Middle English: via Old French desert, from deservir 'serve well' (see deserve).